Fuse



W. A. MILLER Sept. 2 1924.

FUSE

Fllei April l. 1921 Patented Sept. 2, 1924.

WILLIAM .AUGUST MILLER, OF MONACA, PENNSYLVANIA.

FUSE. i

Application iled`Apri1- 1,

To all whom t may concern.' A

Be it known that I, VILLIAM A. MILLER, a. citizen of the United States, and resident of Monaca, in the county of Beaver and State of Pennsylvania, have invented certain new and useful'Improvements in Fuses, of which the following is a specification.

My invention relates to improvements in electric fuses of the removable cartridge type of construct-ion, and it consists in the combinations, constructions and arrangements herein described and claimed.

An object of my invention is to provide a magazine fuse in which a plurality of extra fusible elements are held in reserve and in position to be used selectively or successively to carry the load of an electric current.

A further object of my invention is to provide a magazine fuse which is adapted 'to hold a plurality of fusible elements, any one of which can berendered operative With- 'out disassembling the fuse and without the use of any tools.

A still further object of my invention is to provide a magazine fuse which can be quickly and easily reloaded without the use of any tools and which is thoroughly practical commercially.

Other objects and advantages will be apparent from the following description, and the novel features of the invention will be particularly outlined in the appendedv claims.

My invention is illustrated in the accompanying drawing, forming a part of this -application, in which- Figure 1 is a. perspective view of a fuse embodied in the invention,

Figure 2 is a longitudinal section through the fuse shown in Figure 1',

Figure 3 is a transverse section along the line 3-8 of Figure 2,

Figure 4 is a perspective view, showing the parts of the fuse in disassembled position, and

Figure 5 is a perspective view `of a contact member comprised in the fuse.

Referring now to the drawings, the numeral 1 designates a cylindrical core which is made of any suitable insulating material and which has an axial bore 2 formed therethrough. The core 1 has a plurality of spaced parallel grooves 3 formed in its peripheral wall to extend longitudinally 1921. Serial N0. 457,745.

thereof and each being formed with a counter-bore 4. at one end and a counter-bore 5 at its other end, the counter-bore 5 having a greater length than the counter-bore 4.

A contact member or conducting head which is adapted to be positioned contiguous to the end of the core 1 provided with the counter-bore 5 comprises a substantially cylindrical body 6 having an integral annularportion 7 extending from one end and being provided with a contact projection 8 and with spacing projections 9 which are of less length than the contact projection 8. An annular shoulder 10 is thus defined at the juncture of the body 6 and the annular extensions 7.

A bushing made of insulating material comprises a body 11 conforming in contour to and interitting an axial socketA 12 in the outer end of the body 6 so that an annular extension 18 to the body of the bushing is received in a bore 14 which extends from the bottom of the socket 12 through the extension 7, as shown. The socket 12 is noncircular in sectional contour as is the outer wall of the body 11. The latter is provided with a squared axial opening 15 extending for a distance from its outer end and then being reduced at 1G and merged into an axial bore 17 extending through the extension 13. The bore 17 andthe bore 2 of the core 1 are substantially equal diametrically.

A conducting head or contact member adapted to be arranged at the end of the core 1 provided with the counter-bore 4 comprises a substantially cylindrical body 18 having a cylindrical extension 19 at its inner end, thereby defining an annular shoulder 20. The body 18 is provided with a noncircular opening or socket 21 extending axially from its outer end for a distance and then being reduced at 22 and merged into an axial bore 23 extending through the extension 19, where-by the latter is annular in form.

A bushing made of insulating material comprises a body 24 inter-fitting the socket 21 and being providedavith a reduced extension 25 at its inner end, which extension is adapted to the bore 23. The body 24 of the bushing is provided with a socket 26 of non-circular cross sectional contour which extends axially from the outer end of the body 24 for a distance and is merged at 27 adapted to register with a selected groove 3 of thecore '1 when the latter is disposed within the sleeve 29 and is provided with enlarged end portions 31-31 adapted to overlie the counter-boresvat the opp'osite i ends of thegroove 3 with which the slot 30 is in registry.

' The parts of the lfuse describedso far are shoulder 16.

held in assembled relation by a bolt 32 having a head 33 adapted to the socket 15 and arshank adapted tol be journaled in the aligned bores ,"2 and 2S, and to threadedly engage a 'n'ut`f34which is adapted to the socket 26. In assemblying the fuse, the bushings are placed in the respective conducting heads or contactmembers and the bolt 32 is projected through the bore* 17 so that the head 33 'is disposed within the socket 15 in abutting yrelation to the The core 1 is then mounted upon the shank of the bolt and arranged relatively to the body 6 so that the contact projection 8 extends into one of the counterbores 5. The sleeve 29 is then slipped over relation to the shoulder 10. The body 6 with the bushing therefor fitted therein and with the nut 34 disposed inthe socket 26 is now held against turning and ,the projecting end portion of the shank of the bolt is moved through the bore'28 into engagement with the nut 34. The bolt is then turned by rotating the body 6 until the proximate end of the sleeve 29 is mountedupon the annular extension 19 and abuts the shoulder 20, the opposite end of the sleeve 29 being at this time adjacent to butfnot necessarily in abutting relation to the shoulder 10.

My invention contemplates the use of fusible elements, such-as indicated at 35 in the drawing. Each .of the fusible elements 35 has a straight body provided with enlarged end portions or heads 36-,-36. Thev body of each fusible element 35 isfadapted to each groove 3 of the core 1 so that one of the heads 36 isdisposed within and fills the counter-bore 4A at the end of the groove 3 while the other head 36 is disposed within the counter-bore 5 ofthe groove 3 andterminates at a distance from the outer endof the counter-bore 5 equal to the length of the contact projection 8.

To load the fuse, the sleeve 29is rotated relatively to the core 1 until the slot 30 is fusible element.

in registry with one of the grooves 3. One of the fusible elements 35 is then inserted through the slot 30 into the underlying groove 3 and is disposed in the latter and in the counter-bores at the ends thereof in lowing manner. The body 61s held against turning and the body 18 is turned to tighten the nut on the bolt 32 so that the core 1v will be clamped between the head of theffu'sible element disposed within the counter-bore 4 and the spacing projections 9 while the contact projection 8 will be in contact with the head 36 of one fusible element while all the heads of the fusible elements which are disposed within the counter-bores 4 Will'be in contactjwith the annular extension 19 to the body 18. It will thusA be manifest that an electric current 'may passv from the contact member 13 to allthe heads 36 disposed kin the'counter-bores 4 and a selected, fusible element to the contact projection 8 and Valong the latter to the'body 6, or vice versa.

Then the fusible element'in operative position` has blown, a reserve fusible elel j ment held within one of the chambers of the the core 1 and the extension 7 into abutting core yis rendered operative as follows. The nut 34 is loosened by `turning thefbody 6 while the body 18 is held until the'projection 8 can bewithdrawn from the chamber containing theV blown fusible element.

The body 6 is then rotated until the pro-y jection 8 is in position to enter a selected chamber in which areserve fusible element is disposed. The nut 34 is then tightened in the manner described to clamp the projection 8 against the head of the selected If desired, 'the sleeve 29 may be rotated until the slot 30 is in position with the chamber containing the fusible element to be rendered operative and the position of the contact projection 8 in relation to the selected fusible element conveniently observed.

It will thus be manifest that great economy is effected by my invention. The core 1 f may be formed with any desired number of chambers for the fusible elements and the fuse in which the core iscomprised used continuously with but such interruptions to the service for which intended as are necessary to render the several fusible elenients operative selectively or successively in the manner described and to permit of the reloading of the fuse when certain or all-vof the fusible elements have been blown Cal The expense attendant upon the use of my improved fuse in the manner described Will be relatively small, being restricted to the cost of the fusible elements used during a given period of service. The dimensions of the parts of my improved switch are preferably suoli as to render the switch suitable for use With clips and fittings of standard sizes.

Obviously, my invention is susceptible of embodiment in forms other than thatl in which illustrated in the accompanying drawing, and l therefore consider as my ovvn all modifications and adaptations of the form of the device disclosed herein Which fairly fall Within the scope of the appended claims.

Having thus described the invention what I claim is th l. A fuse comprising a substantially cylindrical core made of insulating material and having an axial bore, said core being formed Wit-h a plurality of spaced parallel grooves extending` longitudinally of the core and being counter-bored at the ends of the core, the counter-bore at oneend of each groove being longer than the counterbore at the opposite end of the groove, fusible elements adapted to be disposed in said grooves and having enlarged end portions disposed in the counter-bores at the ends of said grooves, the smaller counter-bores being completely filled and the larger counterbores being partially filled by the portions of the fusible elements disposed therein, the fusible elements terminating short of the outer ends of the longer counter-bores, con tactI members adapted to abut the opposite ends of the core, the contact member for the end of the core provided with the longer counter-bores having a. projection adapted to enter a selected counter-bore to contact the fusible element disposed therein, and means extending' through the axial bore of said core and connecting the Contact members for releasably holding' said contact members in abutting relation to the ends of said core and ivith the said projection of one of the contact members disposed in a selected counter-bore.

2. A fuse comprising a substantially cylindrical core made o'l insulating material and having an axial bore, said core being formed With a plurality of spaced parallel grooves extending' longitudinally of the. core and being counter-bored at the ends of the core, the counter-bore at one end of each groove being longer than the counter-bore at the opposite end of the groove, fusible elements adapted to be disposed in said grooves and having enlarged end portions disposed in the countenbores at the ends of said grooves, the smaller counter-bores being completely filled and the larger coun- `-ter-bores being partially filled by the portions of the fusible elements disposed therein, the fusible elements terminating short of the outer ends of the longer counterbores` Contact members adapted to abut the opposite ends of the core, the contact member for the end of the core provided with the longer counter-bores having a projection adapted to enter a selected counter-bore to contact the fusible element disposed therein, means extending through the axial bore of said core and connecting the Contact members for releasably holding said contactniembers in abutting relation to the ends of said core and With the said project-ion of one of the contact members disposed in a selected counterebore, and an insulating sleeve spanning said contact members and concentric ivith said core, said sleeve having an opening therethrough adapted to register With said grooves, as said sleeve is rotated relatively to thel core and through ivhich the fusible elements can be fed to said grooves.

A fusel comprising a core made of insulating material and formed with a plurality of spaced grooves in its outer surface extending longitudinally thereof, each of said grooves being provided with a shoulder located at a determined distance from the adjacent end of the groove, the shoulders adjacentl to opposite ends of the core being located at different distances from the corresponding ends of the core. a fusible element for each groove, each fusible element being adapted to be disposed in said groove and having' end portions adapted to engage with said shoulders to hold the fusible element Within the groove so that one end of the fusible element is flush with the corresj'ionding end of the core and the other end of the fusible element is spaced from the second. end of the core, a contact member for the end of the core. having the shoulders located relatively near to the` end, said contact member being adapted to abut the adjacent ends of the fusible elements. a contact element for the second end of the core and having a projection adapted to be projected into a selected one of the grooves into abutting relation to the adjacent end of the fusible element in the said one groove, and cooperative .means carried by the core and the contact members for releasa-bly holding the latter in abi'itting relation to the opposite ends of the Core.

4. A fuse comprising a core made of insulating material and formed With a plurality of spaced grooves in the outer Wall thereof` said grooves extending the entire length of the core, a fusible element for each groove, said fusible element being adapted to be disposed in the groove and being shorter than the groove, said grooves and said fusible elements being formed to co-engage in such manner as to hold the fusible elements flush with one end of the core and short of the to he -fusible element therein and having spacing members engaging with the idylcent end of lthe ooie` and ineens for releasably holding the Contact members clamped meinst the ends of the core.

WiLLiAM AUGUST MILLER 

